Domestic cats are the main reservoir of Bartonella henselae. Epidemiological studies showed bacteria prevalence ranging from 15% to 55% in many countries, including Europe, United States, Asia, Australia and Africa.

No direct transmission from cat to cat in a flea-free environment and no vertical transmission from infected queens to their kittens have been observed.

No obvious clinical signs have been reported in cats naturally infected with B. henselae. Signs only in experimentally infected cats.